This invention relates generally to methods and systems to monitor laser safety and to extend battery usage in a medical device. More particularly, the invention relates to methods and systems using a reflected light sensor in a medical device to ensure eye safety and/or to control signal sampling rate such that battery life may be extended.
Systems having one or more lasers are used in a variety of applications, including industrial and medical applications. For example, devices with lasers are used as data transmitters in optical networks and are used in surgical devices to treat topical dermatological lesions such as port wine stains, warts or tumors on a patient's skin.
In general, laser-containing devices ensure eye safety by employing a redundant electrical circuit that monitors either the laser current or the laser output through a monitor photodiode. An alternative method to ensure eye safety uses a laser communication system that detects an interfering object in the optical path to shut off the laser or reduce the power of the laser to a safe level. Yet another method employed in surgical devices used to treat skin legions deactivates the laser if no solid surface is within about 6 to about 12 inches from the radiating tip of the laser hand piece. Existing laser safety systems, however, are large in size and typically do not use components that perform multiple functions.